Our goal is to determine by morphologic, genetic, biochemical, and immunologic means whether the JHK virus, an enveloped, 80-nm, RNA virus produced constitutively by a B lymphoblastoid cell line established in our laboratory, is a new human retrovirus. If the evidence obtained substantiates its novelty, additional goals will include exploring in depth its biology and molecular genetics and establishing its possible relationship to human disease, especially chronic fatigue immune deficiency syndrome (CFIDS), leukemia, and lymphoma. Future long-range goals include the study of is molecular epidemiology, possible oncogene involvement, and the role of cytokines and transforming or growth factors in JHK-infected cells. The salient features of our putative new virus must be compared with those of known retroviruses. Our specific aims, therefore, are to investigate JHK virus: (i) ultrastructure; (ii) nucleic acid; (iii) antigenic nature in relation to known human retroviruses (HTLV-I and -II and HIV); (iv) reverse transcriptase; (v) infectivity for various somatic cells; and (vi) reactivity with serum from J.H. and selected patients in order to help determine its possible role in humans disease. Since the JHK-3 cell line also contains Epstein- Barr virus DNA and nuclear antigen and a 196-nm viral particle of unusual morphology, this particle will be identified and its relationship determined, if any, to JHK viral infection. To achieve these aims we intend to: (i) analyze viral fine structure by electron microscopy; (ii) clone JHK virus by transfection; (iii) characterize the viral RNA; (iv) clone a cDNA copy of the viral RNA for sequencing and creation of probes; (v) clone the reverse transcriptase gene by PCR; (vi) produce antiviral polyclonal and monoclonal antibodies; (vii) identify specific JHK viral antigens; (viii) test for specific antibodies in selected patient groups; and (ix) probe, as the reagents are developed, for the presence of the virus in peripheral mononuclear cells of selected patients by appropriate hybridizations and after DNA amplification by the polymerase chain reaction.